The debt has steadily and sharply risen since Reagan, you are linking to a chart that shows deficit spending. They are two different things. Debt is the total amount of money owed by the government, deficit is the amount of spending that exceeds revenue. What happened to cause the deficit to jump? Could it possibly be the Bush tax cuts, which are still in effect?
I think you are under the impression that Republicans are actually fiscally responsible, that they will not spend money they don't have, when the truth is, they will just spend it on different things (than Democrats). Neither party is really all that concerned with cutting costs, because they don't want to step on the toes of the people who are really in power - the people who finance their campaigns. They'd rather all of us remain uninformed or better yet, misinformed.